for anyone having trouble unlocking a dell latitude e6420 bios heres is a code i got from a paid service. i dont know if this code will help or work on another system but you can try anyways. i also have a service tag that ends with 1D3B
Password is case-sensitive
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Master password: 0qf9XFXwHgLQneod
After typing your password to accept hold left CTRL and holding press ENTER key twice.
(in some cases just hit only ENTER key)
Passwords are for QWERTY keyboard only (standard US)
If your keyboard is in different type - connect usb QWERTY and try again!
Write it to notebook carefully,take care about zero , big letter o, big letter i, small letter L.
0 - ( digit )
q - quebec ( lowercase )
f - foxtrot ( lowercase )
9 - ( digit )
X - X-RAY ( UPPERCASE )
F - FOXTROT ( UPPERCASE )
X - X-RAY ( UPPERCASE )
w - whisky ( lowercase )
H - HOTEL ( UPPERCASE )
g - golf ( lowercase )
L - LIMA ( UPPERCASE )
Q - QUEBEC ( UPPERCASE )
n - november ( lowercase )
e - echo ( lowercase )
o - oscar ( lowercase )
d - delta ( lowercase )
If you have trouble typing your password or you made a mistake:
After typing your password to accept hold left CTRL and press ENTER key twice,
Turn the laptop off and restart and re-try the password using a USB keyboard QWERTY layout.